The present invention relates to the friction ring of a friction rotor for a friction false-twisting device which is used for the false-twisting of synthetic threads.
Federal Republic of Germany DE-OS No. 29 01 408 shows a friction rotor having a carrier or body, e.g. a disk, which has a V-shaped groove on its outer circumference, and a correspondingly shaped friction ring is arranged in that groove. The friction ring is snapped into the V groove with a preset initial tension. Because the friction rotor is in this form, when its friction ring becomes worn, it can be replaced with a new one, without great trouble and without damage to the carrier.
The above friction ring, however, has the disadvantage that it can only be used at low speeds of rotor rotation. At high speeds of rotation, the friction ring would lift off from the carrier body. Fatigue phenomena as well as the temperatures occurring upon the false twisting affect the unsecured friction ring and contribute to a change in its position. This strongly impairs the trueness of its rotation and roundness of its peripheral surface. Defective yarn is produced. Another disadvantage is that the avivage passes beneath a friction ring which is no longer tightly applied. This can also lead to the premature failure of the ring.